In mid-August, Austrian Foreign Minister Karin Kneissl danced with Russian President Vladimir Putin at his wedding – an act of goodwill that raised eyebrows in a deeply skeptical continent towards Russian foreign policy a few months after an alleged attempt to murder on a former Russian spy in England.

But now Austria has been irritated by its own accusations to the Kremlin's subterfuge. And on Friday the Austrian government announced that Kneissl had canceled a trip to Russia scheduled for next month and convened the Russian business manager.

The Austrian authorities claim to have discovered that a retired army colonel had spied on Russia for several decades, starting in the 1990s and continuing up to this year. The newspaper Krone reported that the nameless colonel had been paid the equivalent of $ 340,000 for private details on Austrian artillery and aeronautics systems. He could be sentenced to two years in prison if found guilty.

Chancellor Sebastian Kurz told a press conference on Friday that if the allegations were upheld, it would not improve the already tense relationship between Russia and the European Union. "Espionage is unacceptable," he said, according to the Austrian press agency.

Kneissl also offered a warning that if the Austrian government's suspicions were correct, it would place "a serious burden on bilateral relations between Austria and Russia".

Russia has denied any knowledge of the spy scandal and has summoned the Austrian ambassador to ask for explanations. Foreign Minister Sergey Lavrov told reporters that Austria has broken international communications regulations and conducted a "megaphone diplomacy" by publishing the allegations so quickly.

"They accuse us in public and then ask for public explanations about a problem we know nothing about," said Lavrov, according to the Russian news agency.

The scandal could mark a turning point in relations between Russia and the new Austrian government. Previously, Vienna had sought neutrality in foreign affairs, trying to maintain links with both Russia and its allies in the European Union. But when a coalition of the center-right People's Party and the far-right Party of Freedom gained control of the government last year, the country took a series of positions that seemed designed to move closer to Moscow.

In the aftermath of the poisoning of double agent Sergei Skripal and his daughter in Salisbury, England, this year, many Western nations have expelled Russian diplomats. But Austria does not – and has expressed opposition to E.U. sanctions against Russia.

Kurz also took a stance on migrations and other issues at European level that opposed him to powerful European leaders like the German Angela Merkel – moves that were warmly welcomed not only by a Kremlin often in conflict with Europe, but also from President Trump's ambassador to Germany, Richard Grenell, who called the young Austrian chancellor a "rockstar".

The country was seen as a possible link between Moscow and Washington and was presented as the venue for a meeting between Putin and Trump. In the end Finland was chosen.

The Austrian Defense Minister, Mario Kunasek, said on Friday that the alleged spy came to light only a few weeks ago, following a suggestion from a friendly intelligence service. Although the Austrian authorities did not appoint the country that provided the information, the newspaper Der Standard reported that it came from German intelligence officials.

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